Planning guidance for loft conversion planning permission in Harrow, Greater London.
Loft conversions may be permitted development subject to limits and conditions set out in permitted development rights.
Additional roof space must not exceed 40 cubic metres for terraced houses or 50 cubic metres for detached and semi-detached houses.
Roof extensions are not permitted on the principal elevation of a house that faces a highway.
The extension must not be higher than the highest part of the existing roof.
The eaves of the extension must be no higher than the eaves of the existing roof.
Materials used for the exterior of the loft conversion should be similar in appearance to those used on the existing house.
Any side-facing windows must be obscure-glazed and non-opening unless the opening parts are more than 1.7 metres above the floor level.
Verandas, balconies and raised platforms are not permitted development.
Roof enlargements must be set back at least 20 centimetres from the original eaves measured along the roof plane.
Side-facing roof extensions are not permitted development.
Planning applications for loft conversions in Harrow may be refused for a variety of reasons depending on the design of the development and local planning policies.
Before starting a loft conversion project in Harrow, homeowners should check the following planning considerations: